She has a great distaste for cell phones, and will hand out detentions to any student she catches using one. Her detentions include the detainees having to help make props and paint sets for the drama club.
Ms. Darbus dislikes Coach Bolton and the two are constantly fighting. She dislikes anything to do with basketball. This seems to change after Troy wins the callback as she personally congratulates him on winning the big game and is excited when the team wins in the third movie although she mixes up a few terms. She also seems to at least set aside her dislike for Coach Bolton as they aren't seen arguing again and even share a laugh when they use each other's congratulatory terms for Troy.
In High School Musical 3: Senior Year, in which the students have started calling her "Ms. D.", she hands out offers of Julliard scholarships to Kelsi Nielsen, Sharpay, Ryan, and Troy Bolton. Later she says that she made out that offer she gave to Troy. Unlike the first movie, she seems to like him. She gives him advice after revealing she was behind his Julliard application and even says Troy is very comfortable on stage. By the third film, she does seem to have lost her status as the "bad guy" and is very supportive of "her kids."
"Proximity to the arts is cleansing for the soul." - High School Musical
"Is there something wrong?" - Ms. Darbus to Troy
"We'll call it Senior Year" - Ms. D to the Drama club
"The Spring Musicale is all about you [travels with basketball], Mr Danforth" - Ms. D to Chad